Bengali Calendar

Bangladesh

Bengali calendar is used in and India's eastern states of West Bengal, Assam and Tripura
The Bengali year is always 593 less than the year in the Gregorian calendar of the Christian Era or Anno Domini era or Common Era or Current Era for the period after Pôhela Boishakh. However, the Bengali year is 594 less than the Gregorian year if it is before Pôhela Boishakh.
History

King Shashanka of Ancient Bengal, who ruled approximately between 590 AD and 625 AD, is credited with starting the Bengali era. Shashanka was the sovereign king of Bengal at the start of seventh century. Much of today’s Indian states of Bengal, Bihar, and Orissa was under his kingdom.

Mughal Emperor Akbar, who ruled from 1556 AD until 1605 AD, and one of his councillor Fatehullah Shirazi are credited with modifying the new Bengali calendar for tax collection purposes.
Months

The names of the twelve months of the Bengali calendar are based on the names of the  nokkhotro (lunar mansions): locations of the moon with respect to particular stars during the lunar cycle.

The names of the months are:

•    ????? Boishakh
•    ??????? Joish?ho
•    ????? Asha?h
•    ?????? Srabon
•    ????? Bhadro
•    ?????? Ashshin
•    ??????? Kartik
•    ????????? Ôgrohaeon
•    ??? Poush
•    ??? Magh
•    ??????? Falgun
•    ????? Choitro